Drier particularly for photographic sheet material



A. KRUGER March 14, 1967 DRIER PARTICULARLY FOR PHOTOGRAPHIC SHEETMATERIAL 6 Sheets-Sheet 1 Filed April 15, 1964 Nip Dam; Jim HT A. KRUGER3,308,555 DRIER PARTICULARLY FOR PHOTOGRAPHIC SHEET MATERIAL March 14,1967 Filed April 13, 1964 5 Sheets-Sheet 2 wmvro/ nmdkko'aek A. KRUGERMarch 14, 1967 DRIER PARTICULARLY FOR PHOTOGRAPHIC SHEET MATERIAL FiledApril 15, 1964 5 Sheets-Sheet 5 United States Patent 3,308,555 DRIERPARTICULARLY FOR PHOTOGRAPHIC SHEET MATERIAL Alfred Kriiger, Hamburg,Germany, assignor to International Copying Machines Co. m.h-H., Hamburg,Germany Fiied Apr. 13, 1964, Ser. No. 359,385 Claims priority,application Germany, Apr. 13, 1%153, r 23,547 Claims. (Cl. 34-155) Thepresent invention relates to driers.

More particularly, the present invention relates to driers which areparticularly suitable for drying sheet material such as photographicsheet material.

In driers of this type it is conventional to provide a guide means inthe housing of the drier for guiding the sheet material from an inletthrough which the sheet material is introduced into the housing to anoutlet through which the sheet material discharges from the housing, andin addition there is conventionally a heating means in the housing -forheating the sheet material as it moves through the housing.

With driers of the above type it is required that the path along whichthe sheet material moves while it is dried be extremely short. In fact,this path is required to be so short that sheet material in the form ofa photograph or a film strip or the like must at its leading end issuefrom the outlet of the drier before the trailing end of the sheetmaterial has entered through the inlet into the housing. In other words,the path along which the sheet material moves while it is dried must beshorter than the greatest length of the shortest photograph, negative,or the like which is to be dried.

In order to provide an efiicient and complete drying with such a shortpath for the sheet material it is essential to use a high dryingtemperature of over 200 C. in the drying chamber. Experience has shownthat when operating with temperatures on this order the photographicsheet material quite frequently becomes damaged and discolored at theemulsion side of the sheet material.

The present invention recognizes the fact that such damaging of thesheet material takes place at locations where the emulsion side of thesheet material engages the guide means which guides the sheet materialthrough the drying chamber because the guide means itself becomes so hotthat at the place where the guide means engages the sheet material,particularly at the emulsion side thereof, the heat is so great that thesheet material becomes damaged.

It is accordingly a primary object of the present invention to provide adrier of the above type which will not damage photographic sheetmaterial but which will at the same time provide a complete andefiicient drying of the sheet material even though the path along whichthe sheet material moves while it is dried is extremely short.

In particular, it is an object of the present invention to provide astructure of the above type which will cool the guide means whichengages the sheet material to an extent sufficient to prevent the guidemeans from damaging the sheet material while at the same time applyingto the sheet material a temperature sufliciently high to efficiently andcompletely dry the same in the extremely short period of time duringwhich the sheet material passes through the drying chamber.

Furthermore, it is an object of the present invention to use the coolingof the guide means for the sheet material to contribute to the drying ofthe sheet material and to also contribute to the efficient guiding ofthe sheet material through the drying chamber.

It is also an object of the present invention to provide for a structureof the above type a cooling of the guide 3,398,555 Patented Mar. 14,1967 means which will prevent the latter from damaging the sheetmaterial and which in addition will not only contribute to the dryingand guiding of the sheet material but which will also contribute to theelimination of moisture from the interior of the drying chamber.

Also, the objects of the present invention include the provision of astructure which will cool not only the guide means for the sheetmaterial but also other structure which engages the sheet material andwhich might damage the same if such other structure were excessivelyheated.

With these objects in view the invention includes, in a drier,particularly for photographic sheet material, a housing having a pair ofopposed walls respectively formed with an inlet and an outlet which arealigned with each other and through which the sheet material isintroduced into and discharged from the housing. A plurality ofelongated hollow guide members are situated in the interior of thehousing for guiding the sheet material along a given path from the inletto the outlet, and a heating means is also located in the housing forheating the sheet material as it moves along this path. In accordancewith the present invention a conduit means communicates with theinterior of the hollow guide members for directing to the interior ofthe hollow guide members a cooling fluid, so that in this way the guidemembers will be maintained at a temperature low enough to preventdamaging or discoloration of the sheet material, and in particular ofthe emulsion side of photographic sheet material.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings, inwhich:

FIG. 1 is a front elevation of one possible embodiment of a structureaccording to the present invention;

FIG. 2 is a plan view of the structure of FIG. 1 shown in a positionwhere the housing of the drier has been displaced to an open position,so that the details of the structure in the interior of the housing areapparent from FIG. 2;

FIG. 3 is a transverse sectional view of the closed housing taken alongline 33 of FIG. 2 in the direction of the arrows and showing thestructure on an enlarged scale, as compared to FIGS. 1 and 2;

FIG. 4 is a transverse sectional view taken along line 4-4 of FIG. 2 inthe direction of the arrows; and

FIG. 5 is an enlarged perspective illustration of another embodiment ofa drier of the invention, the upper part of the housing of the drier ofFIG. 5, and the structure carried by this upper part being shown at theright half of the upper part in an open position and at the left half ina closed position.

Referring now to the drawings and more particularly to FIGS. 1-4, itwill be seen that the drier illustrated therein includes a housing whichhas a lower part 1 and an upper part 2, these housing parts beinghingedly connected to each other by a hinge 3 so that the housing can bedisplaced between the closed position shown in FIG. 1 and the openposition shown in FIG. 2. In order to facilitate the displacement of theupper part 2 of the housing between the positions of FIGS. 1 and 2 theupper housing part 2 carries at one end a handle 4.

The front and rear walls of the housing are respectively formed with anelongated inlet 5 and an elongated outlet 6 which are aligned with eachother and through which the photographic sheet material or the like canbe introduced into and discharged from the housing. It is to be notedthat the plane at which the lower housing part 1 and the upper housingpart 2 join each other when the housing is closed passes substantiallymidway through the inlet 5 and outlet 6 in alignment therewith so thatthe lower half of the inlet 5 and outlet 6 is formed in the lowerhousing part 1 while the upper half of the inlet 5 and outlet 6 isformed in the upper housing part 2.

A pair of lower rollers 7 and a pair of upper rollers 8 which arerespectively located over and engage the lower roller 7 are locatedwithin the housing with one pair of rollers 7 and 8 in alignment withand located next to the inlet 5 so as to form a pair of feed rollers forfeeding sheet material introduced through the inlet 5 into the in teriorof the housing toward the outlet 6, while the other pair of rollers 7and 8, shown at the right in FIG. 3, are situated in alignment with andclosely adjacent to the outlet 6 so as to form a pair of dischargerollers which will discharge dried sheet material out through the outlet6. The pair of lower rollers 7 are supported for rotary movement in thelower housing part 1 while the upper rollers 8 are supported for rotarymovement in the upper housing part 2.

A guide means is provided for guiding the sheet material for movementalong a given path from the inlet to the outlet, and this guide meanstakes the form of a lower bank of elongated hollow guide members 9carried by the lower housing part 1 and an upper bank of elongatedhollow guide members carried by the upper housing part 2, and it will benoted that these banks of hollow guide members 9 are situated adjacentthe plane at the interface between the housing parts when the housing isin its closed position shown in FIG. 3. A conduit means communicateswith the interiors of the hollow guide members 9, and this conduit meansincludes a lower elongated conduit 10 which extends across andcommunicates with the interiors of the lower bank of hollow guidemembers 9, this conduit 10 being situated beneath the lower bank ofguide members 9, as shown in FIG. 3, and the conduit means furtherincludes an upper elongated conduit 11 extending across andcommunicating with the hollow interiors of the upper bank of conduits 9,this upper conduit 11 being located over the upper bank of conduits 9,as shown in FIG. 3. The upper faces of the lower bank of guide members 9and the lower faces of the upper bank of conduits 9 are each formed witha plurality of openings 12 directed toward the path along which thesheet material moves, so that in this way when a cooling gas such as airis introduced by the conduits 1t? and 11 into the interiors of thehollow guide members 9, this cooling fluid will issue through theopenings 12 toward the sheet material which is guided between the banksof guide members 9.

Below the lower bank of guide members 9 and above the upper bank ofguide members 9 are elongated heating elements 13 which extend parallelto the rollers 7 and 8 and which take the form of, for example,electrically conductive resistance wires which when supplied withcurrent will heat the interior of the housing 1, 2. A pair of reflectors14 in the form of elongated troughs are arranged as shown in FIG. 3 withtheir concave surfaces directed toward the heating elements 13 so thatthe heating rays will be reflected by the reflectors 14 toward the sheetmaterial guided by the guide members 9, and the upper reflector 14 isformed with unillustrated openings through which heated humid air canpass upwardly, the top wall of the housing being formed with openings 15through which the hot humid air will pass to the exterior of the heaterso that in this way moisture will be removed therefrom.

The ends of each guide member 9 are respectively formed with a pair ofadditional openings 23, and these openings are directed toward therollers 7 and 8 so that in this way the cooling fluid will also cool therollers 7 and 8.

All of the above-described structure is located in a drying chamber ofthe housing which is separated from a fan chamber 17 thereof by apartition 16 divided into a pair of sections respectively carried by thelower and upper parts of the housing. When the housing is in the closedposition as shown in FIG. 3 the sections of the partition 16 engage eachother so as to form a continuous partition separating the fan chamber 17from the remainder of the interior of the housing which forms the dryingchamber. It is to be noted that many of the above elements such as theelongated reflectors 14 and the conduits 1d and 11 are supported attheir ends by an end wall of each housing part 1 and 2 and the partition16, and the guide elements 9 may be supported by the edges of thereflectors 14- as well as by the conduits 1i) and 11. The rollers 7 and8 respectively have their ends supported for rotary movement in bearingscarried by the partition sections 16 and the ends of the housing parts 1and 2 which are distant from fan chamber 17.

The end wall of the lower housing part 1 which defines part of the fanchamber 17 is formed with an air inlet 18, and a fan 19 is located inthe fan chamber and driven by a motor 22 in a direction which causes thefan 19 to suck air into the interior of the chamber 17 through the airinlet 18. This air which is in this way sucked into the chamber 17 isdelivered into the interior of the conduits 1t and 11, and as may beseen from FIG. 4 the conduit ltl has an Open end communicating with theinterior of the chamber 17 through the lower section of the partition16. In the same way the upper conduit 11 communicates at one end withthe interior of the chamber 17 through the upper section of thepartition 16, and thus the air which is sucked into the chamber 17 bythe fan 19 will be driven by the latter into the conduits 10 and 11 toflow therefrom into the interiors of the several guide elements 9 fromwhere the air will issue through the openings 12 to the path along whichthe sheet material moves and through the openings 23 to the rollers 7and 8.

The lower rollers 7 have ends which extend through the lower section ofthe partition 16 into the chamber 17 where these ends respectively carrya pair of sprocket wheels 20, as shown most clearly in FIG. 4,and themotor 22 which drives the fan 19 also drives through a suitablestep-down transmission an endless chain 21 which rotates the sprockets2t and thus rotates the roller 7 in the same direction for advancing thesheet material from the inlet 5 toward the outlet 6. The upper rollers 3are turned only by frictional engagement with the rollers 7 or withsheet material between the rollers 7 and 8.

After the drier has been started so that the heating elements 13 areenergized and the motor 22 is running, a sheet material which is to bedried is introduced through the inlet 5 into the interior of the housingto be fed therethrough by the feed rollers 7 and 8 which are adjacentthe inlet 5, and as the sheet material moves beyond the feed rollers 7and 8 shown at the left of FIG. 3 the sheet material will pass betweenthe upper and lower banks of guide elements 2 to be guided therebytoward the outlet 6. In this way the sheet material will progress to thedischarge rollers 7 and 8 which are adjacent the outlet 6 to bedischarged by the discharge rollers out through the outlet 6. During itsmovement through the drier the sheet material is dried by the heatingrays produced by the heating bars or wires 13 as well as by the airwhich is directed toward the sheet material through the openings 12.This air while cooling the guide elements 9 is of course inheat-exchanging relation therewith so that the air becomes heated andthus it is air at an elevated temperature which is directed from theopenings 12 against the sheet material to contribute to the dryingthereof as well as to the ease with which the sheet materialrmoves alongthe path defined between the banks of guide elements 9.

The embodiment of the invention which is illustrated in FIG. 5 operateson the same principle as the embodi- 'ment thereof illustrated in FIGS.14 and described above. However, in the embodiment of FIG. 5 the upperpart 2 and the lower part 1 of the housing are hingedly connected toeach other by hinge elements 3 which are connected to the longitudinalside of the housing parts 1 and 2, as is apparent from FIG. 5.

Moreover, instead of a single lower conduit and a single upper conduit11, the embodiment of FIG. 5 includes a pair of lower conduits 10' and apair of upper conduits 11, and these conduits each have a trapezoidalcross section and are arranged so that their widest wall extendsvertically, and it will be noted that the wider vertical walls of theconduits are directed away from each other while the shorter verticalwalls are directed toward each other so that in this way the upper pairof conduits 11 respectively have a pair of lower inclined walls whichare inclined away from the front and rear walls of the housing upwardlytoward the interior thereof while the lower pair of conduits 19' haveupper inclined walls which extend in a direction from the front and rearwalls of the housing downwardly toward the interior thereof. These upperinclined walls of the conduits 10 are fixed to the opposed ends of thelower bank of hollow guide members 9 so as to support the latter, andthese guide members 9 have open ends which communicate through the wallsof the conduits 10 with the interior thereof, and in the same way theupper bank of conduits 9 extend between and are carried by the lowerwalls of the conduits 11, the upper bank of guide members 9 also havinghollow ends which communicate with the interiors of the conduits 11'.

In the embodiment of FIG. 5, the openings 23 through which air issues tocool the rollers 7 and 8, instead of being formed at the ends of theguide members 9, are formed adjacent the lower corners of the conduits11' and the uppermost corners of the conduits 10, and all of theseopenings 23' are directed toward the rollers 7 and 8 so that in this waycooling fluid will issue from the conduits 10' and 11' toward and intoengagement with the rollers 7 and 8 to maintain the latter at atemperature low enough to prevent injury to the sheet material, in thesame way that the rollers 7 and S of FIGS. 14 are maintained at atemperature low enough to prevent injury to the sheet material.

FIG. 5 illustrates in the upwardly turned portion of the upper housingpart 2 a sensing element 24 of a thermostat, this element 24 sensing thetemperature in the interior of the housing and preventing thetemperature in the interior of the housing from moving above apredetermined upper limit. In this case the thermostat, which isconventional, is electrically connected in a known way into the circuitof the heating elements 13 to control the temperature thereof, and thisthermostat will maintain the temperature of heating elements 13 betweenpredetermined limits by automatically opening the circuit at an uppertemperature limit and closing the circuit at .1 lower temperature limitof the heating elements 13.

In the embodiment of FIG. 5, instead of elongated trough-shapedreflectors, the reflectors 14 are in the form of plates 14'. The upper.plate 14' is fixed to and supported by the conduits 11' substantiallyat the junction between the inner vertical wall thereof and the lowerinclined walls While the lower plate 14' is fixed to and carried by thelower conduits 10' substantially at the junction between the innervertical walls thereof and the upper inclined walls of these conduits15'. At least the upper reflector 14' is formed with openings throughwhich the hot humid air can pass upwardly to the openings in the topwall 2 so as to move out through these latter openings to the exteriorof the drier,

Furthermore, the upper rollers 8 in the embodiment of FIG. 5 are notsupported for rotary movement in the upper housing part 2. Instead theyremain at all times with the lower housing part 1 and are supported insuitable brackets so as to remain above and in engagement 6 with thelower rollers 7. Thus, it will be seen that the upper rollers 8terminate in free ends guided in vertical notches formed in bearingblocks 26 which are carried only by the lower housing part 1. Theseupper rollers 8 simply rest by their own weight on the lower rollers 7,respectively.

Except for the above-noted differences, the embodiment of FIG. 5 is thesame as that of FIGS. 14.

With the structure of the invention it is possible to maintain theinterior of the drying chamber at a temperature between 200 and 300 C.The sheet material can pass through the interior at a period of time ofbetween 12 and 15 seconds, to be thoroughly dried, and photographicsheet material having the format DIN A 6 has been preferably dried inthis manner in a period of from 12 to 15 seconds at a temperature rangeof between 2G0 and 300 C.

The heating fluid which issues through the openings of the guideelements provides a turbulence in the air in the drying chamber, andthis turbulence improves the drying action and enhances the movement ofthe sheet material through the housing as well as the flow of damp airout of the drying chamber.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofdriers differing from the types described above.

While the invention has been illustrated and described as embodied indriers for photographic sheet material, it is not intended. to belimited to the details shown, since various modifications and structuralchanges may be made without departing in any way from the spirit of thepresent invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can by applying current knowledgereadily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims. I

What is claimed as new and desired to be secured by Letters Patent is:

1. In a drier, particularly for photographic sheet material, incombination, a housing formed with an inlet and an outlet through whicha sheet material which is to be dried is introduced into and moves outof said housing, respectively; spaced guide means in said housingengaging and guiding sheet material which is to be dried along a givenpath from said inlet to said outlet; heating means arranged in saidhousing for heating the air within said housing so as to thereby heatthe sheet material while it moves along said path, said guide meansengaging the sheet material being also subject to the heating action ofsaid heating means and separate cooling means communicating with saidguide means for cooling the latter to thereby prevent heating of saidguide means above a predetermined temperature beyond which the sheetmaterial engaged by said guide means is susceptible to heat damage.

2. In a drier, particularly for photographic sheet material, incombination, a housing formed with an inlet through which a sheetmaterial to be dried is inserted into said housing and an outlet throughwhich dried sheet material issues from said housing; spaced hollow guidemeans located in said housing for engaging and guiding sheet materialalong a given path from said inlet to said outlet; heating meansarranged in said housing for heating the air within said housing so asto thereby heat the sheet material as it moves along said path so as todry the sheet material, said guide means engaging the sheet materialbeing also subject to the heating action of said heating means; andcooling means, includ ing conduit means communicating with the interiorof said hollow guide means for directing a cooling fluid thereto so asto cool said guide means to thereby prevent heating of said guide meansabove a predetermined temperature beyond which the sheet materialengaged by said guide means is susceptible to heat damage.

3. In a drier as recited in claim 2, said housing having opposed wallsrespectively formed with said inlet and outlet, and said inlet andoutlet being aligned with each other.

4. In a drier particularly for photographic sheet material, incombination, a housing having opposed walls respectively formed with aninlet and an outlet which are aligned with each other and through whichsheet material is respectively introduced into and issued from saidhousing; a plurality of spaced elongated hollow guide members located insaid housing for engaging and guiding sheet material along apredetermined path from said inlet to said outlet; heating meansarranged in said housing for heating the air within said housing so asto thereby heat the sheet material moving along said path; and separatecooling means, including conduit means communicating with the interiorsof said elongated hollow guide elements for directing into the latter acooling fluid to thereby prevent heating of said guide means above apredetermined temperature beyond which the sheet material engaged bysaid guide means is susceptible to heat damage.

5. In a drier, particularly for photographic sheet material, incombination, a housing having opposed walls respectively formed with aninlet and an outlet which are aligned with each other so that sheetmaterial which is to be dried can be introduced into said housingthrough said inlet and can issue from said housing through said outlet;a plurality of spaced elongated hollow guide members located in saidhousing for engaging and guiding sheet material along a given path fromsaid inlet to said outlet, said guide members each being formed with aplurality of openings directed toward said path; heating means arrangedin said housing for heating the air within said housing so as to therebyheat, and thus dry, sheet material moving along said path; and separatecooling means, including conduit means communicating with the interiorsof said guide members for directing into the latter a cooling gas whichcools said guide members and which issues through said openings thereofinto the interior of said housing toward said path to thereby preventheating of said guide means above a predetermined temperature beyondwhich the sheet material engaged by said guide means is susceptible toheat damage while the cooling fluid itself, after acquiring heat, willcontribute to the drying of the sheet material.

6. In a drier, particularly for photographic sheet material, incombination, a housing having a pair of opposed Walls respectivelyformed with an inlet and an outlet which are aligned with each other andthrough which sheet material which is to be dried can be introduced intoand will discharge from said housing; a pair of feed rollers located insaid housing in alignment with said inlet thereof and adjacent to saidinlet for receiving the sheet material introduced through said inlet andfeeding the sheet material toward said outlet; a pair of dischargerollers located in said housing in alignment with and adjacent saidoutlet for receiving sheet material which has moved from said inlettoward said outlet and discharging the same through said outlet; aplurality of spaced elongated hollow guide members located in saidhousing between said feed rollers and discharge rollers for engaging andguiding sheet material along a given path from said inlet to saidoutlet, said hollow guide members each being formed with openingsdirected toward said path and directed toward said feed and dis chargerollers; heating means arranged in said housing for heating the airtherewithin to thereby heat the sheet material, said guide membersengaging the sheet mate- .rial being also subje t P0 the heating actionof said heating means and separate cooling means, including conduitmeans communicating with said guide members for directing into thelatter a cooling fluid which cools said members and which issues throughsaid openings thereof to also cool said rollers to thereby preventheating of said guide means above a predetermined temperature beyondwhich the sheet material engaged by said guide means is susceptible toheat damage.

7. In a drier, particularly for photographic sheet material, a housingcarrying in its interior a partition dividing the interior of saidhousing into a drying chamber and a fan chamber, a Wall of said housingwhich defines part of said fan chamber being formed with an air inlet,and a pair of opposed walls of said housing which define part of saiddrying chamber being respectively formed with an inlet and an outletwhich are aligned with each other and through which sheet material whichis to bedried is introduced into and discharged from said dryingchamher; a plurality of spaced elongated hollow guide members located insaid drying chamber for engaging and guiding sheet material along agiven path from said inlet to said outlet; heating means arranged insaid drying chamber for heating the air within said housing so as tothereby heat the sheet material moving along said path, said guide meansengaging the sheet material being also subject to the heating action ofsaid heating means; conduit means communicating with the interiors ofsaid guide members and communicating through said partition with saidfan chamber; and cooling means for cooling said guide members, saidcooling means including fan means in said fan chamber for drawing airinto the latter through said air inlet and for discharging air from saidfan chamher into said conduit means to enter therefrom into said hollowguide members for cooling the latter to thereby prevent heating of saidguide means above a predetermined temperature beyond which the sheetmaterial engaged by said guide means is susceptible to heat damage.

8. In a drier as recited in claim 7, a pair of feed rollers locatedadjacent said inlet in alignment therewith in the interior of saidhousing for feeding material introduced through said inlet along saidpath toward said outlet and a pair of discharge rollers located in saidhousing in alignment with said outlet adjacent the latter fordischarging sheet material out of said housing through said outletthereof, each of said pairs of rollers having at least one roller whichextends at an end portion through said partition into said fan chamber,said fan meansincluding a fan and a motor which drives the same, andtransmission means operatively connected to said rollers which extendinto said fan chamber and said motor for transmitting a drive therefromto said rollers.

9. in a drier, particularly for photographic sheet material, incombination. a housing having a pair of opposed walls respectivelyformed with an inlet and an outlet which are aligned with each other andthrough which sheet material to be dried is introduced into anddischarged irom said housing, said housing being divided into two partswhich ioin each other at a plane which passes substantially centrallythrough and is aligned with said inlet and said outlet; spaced guidemeans in said housing for engaging and guiding sheet material from saidinlet to said outlet, said guide means including a plurality ofelongated hollow members; heating means arranged in said housing forheating the air Within said housing so as to thereby heat the sheetmaterial engaged and guided by said hollow members, said guide meansengaging the sheet material being also subject to the heating action ofsaid heating means; and separate cooling means, including conduit meanscommunicating With the interiors of said hollow members for directing acooling fluid into the latter to thereby prevent heating of said guidemeans above a predetermined temperature beyond which the sheet materialengaged by said guide means is susceptible to heat damage.

10. In a drier as recited in claim 9, hinge means operatively connectedto said parts of said housing for hingedly connecting the same to eachother so that one of said parts is turnable toward and away from theother of said parts of said housing.

11. In a drier, particularly for photographic sheet material, incombination, a housing having front and rear walls respectively formedwith an inlet and an outlet which are aligned with each other andthrough which sheet material which is to be dried is introduced into anddischarged from said housing, said housing also having a top wall formedwith openings passing therethrough; a plurality of spaced elongatedhollow guide members located in said housing and extending between saidinlet and outlet thereof for guiding sheet material along a given pathfrom said inlet to said outlet, said guide members being respectivelyformed with openings directed toward said path; heating means in saidhousing for heating sheet material moving along said path; and conduitmeans, including a pair of elongated conduits of trapezoidalcrosssection respectively connected to and communicating with opposedends of said elongated hollow guide members for directing into thelatter a cooling gas which passes through said openings of said guidemembers to contribute to the drying of the sheet material and which thenpasses out of said housing through said openings in said top wallthereof.

12. In a drier, particularly for photographic sheet material, incombination, a housing having front and rear walls respectively formedwith an inlet and an outlet which are aligned with each other andthrough which sheet material which is to be dried is introduced into anddischarged from said housing; a bank of spaced lower elongated hollowguide members and a bank of spaced upper elongated hollow guide membersextending between said inlet and outlet, said banks of guide membersdefining between themselves a path along which sheet material moves fromsaid inlet to said outlet and being arranged to engage such sheetmaterial during this movement; heating means in said housing for heatingthe air within said housing so as to thereby heat the sheet materialmoving along said path, said guide means engaging the sheet materialbeing also subject to the heating action of said heating means; andseparate cooling means, including at least one pair of conduitsrespectively communicating with said banks of hollow guide members fordirecting cooling fluid into the latter to thereby prevent heating ofsaid guide means above a predetermined temperature beyond which thesheet material engaged by said guide means is susceptible to heatdamage.

13. In a drier, particularly for photographic sheet material, incombination, a housing having front and rear walls respectively formedwith an inlet and an outlet which are aligned with each other andthrough which sheet material to be dried can be introduced into anddischarged from said housing; a lower bank of spaced elongated hollowguide members and an upper bank of spaced elongated hollow guide memberslocated in said housing, said banks of guide members defining betweenthemselves a path along which sheet material is guided during movementfrom said inlet to said outlet and being arranged to engage such sheetmaterial during this movement; heating means in said housing for heatingthe air within said housing so as to thereby heat the sheet materialmoving along said path; one pair of elongated hollow conduitsrespectively communicating with opposed ends of the lower bank ofelongated hollow guide members for directing a cooling fluid into thelatter; and a second air of elongated hollow conduits respectivelycommunicating with opposed ends of the upper bank of elongated hollowguide members for directing cooling fluid into the guide members of saidupper bank; and separate cooling means connected with said pairs ofconduits for supplying cooling fluid thereto so that said conduits willdirect such cooling fluid to said hollow guide means.

14. In a drier, particularly for photographic sheet material, incombination, a housing having front and rear walls respectively formedwith an inlet and an outlet which are aligned with each other andthrough which sheet material to be dried can be introduced into anddischarged from said housing; a lower bank of elongated hollow guidemembers and an upper bank of elongated hollow guide members located insaid housing, said banks of guide members defining between themselves apath along which sheet material is guided during movement from saidinletto said outlet and being arranged to engage such sheet material duringthis movement; heating means in said housing for heating the air withinsaid housing so as to thereby heat the sheet material moving along saidpath; one pair of elongated hollow conduits respectively communicatingwith opposed ends of the lower bank of elongated hollow guide membersfor directing a cooling fluid into the latter; and a second pair ofelongated hollow conduits respectively communicating with opposed endsof the upper bank of elongated hollow guide members for directingcooling fluid into the guide members of said upper bank; and separatecooling means con nected with said pairs of conduits for supplyingcooling fluid thereto so that said conduits will direct such coolingfluid to said hollow guide means; a pair of feed rollers located in saidhousing adjacent and in alignment with said inlet for feeding materialintroduced through said inlet between said banks of guide members towardsaid outlet, and a pair of discharge rollers located in said housing inalignment with and adjacent said outlet for receiving sheet materialwhich has passed between said banks of guide members and discharging thesheet material through said outlet, said conduits respectively beingformed with openings directed toward said rollers for cooling the latterwith the fluid which said conduits direct to the interiors of said guidemembers.

15. In a drier as recited in claim 14, said guide members being formedwith openings directed toward said path and said housing having a topwall formed with openings, said fluid being air so that the airintroduced by said conduits into said guide members will on the one handcool said rollers, will on the other hand pass through said openings ofsaid guide members to said path for contributing to the drying of thesheet material, and will finally pass out of said housing through saidopenings in said top wall thereof.

References Cited by the Examiner UNITED STATES PATENTS 1,930,575 10/1933Wynd et a1. 34-160 X 2,038,457 4/1936 Venturini 34-155 2,391,764 12/1945Andrews 34156 X 2,691,225 10/1954 Kamprath 34156 FOREIGN PATENTS 517,5433/1955 Italy.

FREDERICK L. MATTESON, JR., Primary Examiner. A. D. HERRMANN, AssistantExaminer.

1. IN A DRIER, PARTICULARLY FOR PHOTOGRAPHIC SHEET MATERIAL, IN COMBINATION, A HOUSING FORMED WITH AN INLET AND AN OUTLET THROUGH WHICH A SHEET MATERIAL WHICH IS TO BE DRIED IS INTRODUCED INTO AND MOVES OUT OF SAID HOUSING, RESPECTIVELY; SPACED GUIDE MEANS IN SAID HOUSING ENGAGING AND GUIDING SHEET MATERIAL WHICH IS TO BE DRIED ALONG A GIVEN PATH FROM SAID INLET TO SAID OUTLET; HEATING MEANS ARRANGED IN SAID HOUSING FOR HEATING THE AIR WITHIN SAID HOUSING SO AS TO THEREBY HEAT THE SHEET MATERIAL WHILE IT MOVES ALONG SAID PATH, SAID GUIDE MEANS ENGAGING THE SHEET MATERIAL BEING ALSO SUBJECT TO THE HEATING ACTION OF SAID HEATING MEANS AND SEPARATE COOLING MEANS COMMUNICATING WITH SAID GUIDE MEANS FOR COOLING THE LATTER TO THEREBY PREVENT HEATING OF SAID GUIDE MEANS ABOVE A PREDETERMINED TEMPERATURE BEYOND WHICH THE SHEET MATERIAL ENGAGED BY SAID GUIDE MEANS IS SUSCEPTIBLE TO HEAT DAMAGE. 